If you're doing a mild 427ci build, the LS7 block is all you need. Resleeved LS2's are good for well over 1,000 RWHP.

The stock radiator and cooling system is also all you need. Just put a 160 t-stat in there and have your tuner program your fans to come on sooner when you get the engine in and do the dyno tune on it.

My stock cooling system and my 427ci down here in HOT south Florida runs cool as a cucumber no matter what I'm doing. A/C blasting, in traffic on a 90* day...no problem at all. Its all about having a clean condensor and radiator and a healthy, properly functioning cooling system.

Cost of the LS7 before shipping is $2724 the cheapest I've seen, that's only a couple hundred off the cost of the sleeved LS2, we incorporate all that into the build though. No we don't go with a factory hone job on he LS7, it get's cleaned up to our specs.

Thanks for the info, really for my application the extra strength of the sleeves is not going to make a difference. What is the reliability like on the sleeved motors. The price doesn't seem to be much of an issue with the qoutes that I have recieved so far.

Cost of the LS7 before shipping is $2724 the cheapest I've seen, that's only a couple hundred off the cost of the sleeved LS2, we incorporate all that into the build though. No we don't go with a factory hone job on he LS7, it get's cleaned up to our specs.

Holy moses...a bare LS7 block is $2,724. What a rip off. I never knew they were that much.

If you have an LS1 now, you could consider adding Darton MID sleeves into it and getting to 427 or more. The MID sleeve will be stronger than either the dry sleeve LS2 or LS7 blocks as well. On top, everything you now have, sensors, harness etc will fit with no mods. Cost for MID sleeve operation looks to be around $3K - about the same as the other 2 options as well.

If you build the LS1, tell folks you just have a H/C/I engine and let them try to figure out why it runs so well.

Question, why not an LS3 based 427? Seems this would eliminate the need to re-sleeve.

The added stroke is not desirable for power add applications. LS7 heads and the 4.125 bore is another but that not to say that nice set of heads on the L92 427 wont produce great results as well. Cubic inches are cubic inches when all else is equal.

What I had thought would work is a 427 rotating assembly with cathedral port heads so that I could use my intake and injectors. I live in southern Ontario and would be willing to take the car anywhere from NY to Michigan but can't seem to get the answers from the builders that I have spoken to so far.

FI and nitrous. Other reasons would be sleeve material. The LS7 uses a different sleeve material and we've seen some cylinder cracking issues with detonation (its also unsupported at the top). SO for my money I go with the sleeved LS2, even if the LS7 block was $2500 I'd still use the sleeved LS2.

What I had thought would work is a 427 rotating assembly with cathedral port heads so that I could use my intake and injectors. I live in southern Ontario and would be willing to take the car anywhere from NY to Michigan but can't seem to get the answers from the builders that I have spoken to so far.

What answers are you looking for? reliability? If done right should be no different than any other engine. We just did a 383 for a guy to the North and he had us ship the motor to and the swap was done at Redline iin NY. Maybe that could work for you as well?

What I had thought would work is a 427 rotating assembly with cathedral port heads so that I could use my intake and injectors. I live in southern Ontario and would be willing to take the car anywhere from NY to Michigan but can't seem to get the answers from the builders that I have spoken to so far.

I have a Katech Ls2 Sleeved 427, 4.125 bore/4.0 stroke, I used a set of
TFS 225 and a small cam, 92mm Ported Fast, 525rwhp and 571rwtq, sure is great on the street, it does good at the track too!!

Just had a LS3 427 put together for a hair over $4k Callies 4.1" crank, compstar rods and manley pistons. I also plan on spraying up to a 200 shot on the car. Ha if I blow it up I'll sleeve the block and make it a 440 Plenty of people running this setup with no issues and it might be "undesirable" but its easier on my wallet.

Show me a better price. That was TSP's website and I know SDPC is very close. Not to many places with better pricing unless they have a few blocks left over that they haven't sold or used for a while ( and I haven't seen them anywhere).

They used to be $2500 or so but GM raised the price and between TSP and US and HKE and SDPC and few others we go through a lot of blocks